1. Field of the Invention
The present invention relates to a multi-spark ignition system that includes an ignition coil, an energy storing circuit and a switching member. The switching member is controlled to repeatedly discharge the electric energy stored in the energy storing circuit into the primary coil of the ignition coil, thereby generating multiple ignition sparks at a spark plug that is connected with the secondary coil of the ignition coil.
2. Description of the Related Art
Such a multi-spark ignition system is disclosed in JP-P2811781 or U.S. Pat. No. 5,056,496, which is a counterpart of the former. In the disclosed multi-spark ignition system, both a command signal of energy storing and a command signal of energy discharging period are inputted from an engine control unit (ECU) before the stored electric energy is discharged into the ignition coil so that both the energy storing timing and the energy discharging timing can be controlled according to the engine rotation speed.
However, the multi-spark system and the ECU must be connected by two different signal wires. Accordingly, the number of connectors and other related functions such as a failsafe control increases. That is, such a multi-spark ignition system has to have a complicated and bulky interface.